Merge pull request #102 from Mistobaan/master

use switch.(type) instead

server.go

@@ -538,24 +538,27 @@ func (s *Server) followerLoop() {
 		case e := <-s.c:
 			if e.target == &stopValue {
 				s.setState(Stopped)
-			} else if command, ok := e.target.(JoinCommand); ok {
-				//If no log entries exist and a self-join command is issued
-				//then immediately become leader and commit entry.
-				if s.log.currentIndex() == 0 && command.NodeName() == s.Name() {
-					s.debugln("selfjoin and promote to leader")
-					s.setState(Leader)
-					s.processCommand(command, e)
-				} else {
+			} else {
+				switch req := e.target.(type) {
+				case JoinCommand:
+					//If no log entries exist and a self-join command is issued
+					//then immediately become leader and commit entry.
+					if s.log.currentIndex() == 0 && req.NodeName() == s.Name() {
+						s.debugln("selfjoin and promote to leader")
+						s.setState(Leader)
+						s.processCommand(req, e)
+					} else {
+						err = NotLeaderError
+					}
+				case *AppendEntriesRequest:
+					e.returnValue, update = s.processAppendEntriesRequest(req)
+				case *RequestVoteRequest:
+					e.returnValue, update = s.processRequestVoteRequest(req)
+				case *SnapshotRequest:
+					e.returnValue = s.processSnapshotRequest(req)
+				default:
 					err = NotLeaderError
 				}
-			} else if req, ok := e.target.(*AppendEntriesRequest); ok {
-				e.returnValue, update = s.processAppendEntriesRequest(req)
-			} else if req, ok := e.target.(*RequestVoteRequest); ok {
-				e.returnValue, update = s.processRequestVoteRequest(req)
-			} else if req, ok := e.target.(*SnapshotRequest); ok {
-				e.returnValue = s.processSnapshotRequest(req)
-			} else {
-				err = NotLeaderError
 			}
 
 			// Callback to event.
@@ -635,14 +638,16 @@ func (s *Server) candidateLoop() {
 				var err error
 				if e.target == &stopValue {
 					s.setState(Stopped)
-				} else if _, ok := e.target.(Command); ok {
-					err = NotLeaderError
-				} else if req, ok := e.target.(*AppendEntriesRequest); ok {
-					e.returnValue, _ = s.processAppendEntriesRequest(req)
-				} else if req, ok := e.target.(*RequestVoteRequest); ok {
-					e.returnValue, _ = s.processRequestVoteRequest(req)
+				} else {
+					switch req := e.target.(type) {
+					case Command:
+						err = NotLeaderError
+					case *AppendEntriesRequest:
+						e.returnValue, _ = s.processAppendEntriesRequest(req)
+					case *RequestVoteRequest:
+						e.returnValue, _ = s.processRequestVoteRequest(req)
+					}
 				}
-
 				// Callback to event.
 				e.c <- err
 
@@ -666,7 +671,7 @@ func (s *Server) candidateLoop() {
 	}
 }
 
-// The event loop that is run when the server is in a Candidate state.
+// The event loop that is run when the server is in a Leader state.
 func (s *Server) leaderLoop() {
 	s.setState(Leader)
 	s.syncedPeer = make(map[string]bool)
@@ -688,15 +693,18 @@ func (s *Server) leaderLoop() {
 		case e := <-s.c:
 			if e.target == &stopValue {
 				s.setState(Stopped)
-			} else if command, ok := e.target.(Command); ok {
-				s.processCommand(command, e)
-				continue
-			} else if req, ok := e.target.(*AppendEntriesRequest); ok {
-				e.returnValue, _ = s.processAppendEntriesRequest(req)
-			} else if resp, ok := e.target.(*AppendEntriesResponse); ok {
-				s.processAppendEntriesResponse(resp)
-			} else if req, ok := e.target.(*RequestVoteRequest); ok {
-				e.returnValue, _ = s.processRequestVoteRequest(req)
+			} else {
+				switch req := e.target.(type) {
+				case Command:
+					s.processCommand(req, e)
+					continue
+				case *AppendEntriesRequest:
+					e.returnValue, _ = s.processAppendEntriesRequest(req)
+				case *AppendEntriesResponse:
+					s.processAppendEntriesResponse(req)
+				case *RequestVoteRequest:
+					e.returnValue, _ = s.processRequestVoteRequest(req)
+				}
 			}
 
 			// Callback to event.
@@ -726,16 +734,18 @@ func (s *Server) snapshotLoop() {
 
 		if e.target == &stopValue {
 			s.setState(Stopped)
-		} else if _, ok := e.target.(Command); ok {
-			err = NotLeaderError
-		} else if req, ok := e.target.(*AppendEntriesRequest); ok {
-			e.returnValue, _ = s.processAppendEntriesRequest(req)
-		} else if req, ok := e.target.(*RequestVoteRequest); ok {
-			e.returnValue, _ = s.processRequestVoteRequest(req)
-		} else if req, ok := e.target.(*SnapshotRecoveryRequest); ok {
-			e.returnValue = s.processSnapshotRecoveryRequest(req)
+		} else {
+			switch req := e.target.(type) {
+			case Command:
+				err = NotLeaderError
+			case *AppendEntriesRequest:
+				e.returnValue, _ = s.processAppendEntriesRequest(req)
+			case *RequestVoteRequest:
+				e.returnValue, _ = s.processRequestVoteRequest(req)
+			case *SnapshotRecoveryRequest:
+				e.returnValue = s.processSnapshotRecoveryRequest(req)
+			}
 		}
-
 		// Callback to event.
 		e.c <- err